Achieving the lowest possible noise and electron temperature in quantum circuits
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QFilter-II is your compact solution for advanced multi-stage low-pass filtering. It’s specifically designed to reject noise and maintain millikelvin electron temperatures across 24 signal lines. This makes it an ideal fit for your quantum electronics devices and other sensitive cryogenic circuits. Originating from extensive research at Harvard University and the University of Copenhagen, QFilter is now a trusted tool in over 100 research groups worldwide.
Advanced Filtering and Thermalization Below 1 Kelvin
At millikelvin temperatures, ensuring cold electrons in signal lines is a challenge. QFilter-II addresses this by cooling electrons and filtering out electrical noise ranging from about 65 kHz to tens of GHz. Constructed from gold-coated high-conductivity copper and mountable on your cryostat’s mixing chamber plate, it is a key component for any cryogenic setup.
24 Line Filter Configuration with Optimal Performance
Our standard configuration offers two filtering banks (low-frequency and radio frequency) with 25-pin micro-D connectors. These banks are connected in series using a shielded jumper cable. The compact, non-magnetic design allows for direct mounting on the mixing chamber plate, compatible with most fridge manufacturers such as Bluefors fridges and the Oxford Instrument Proteox shown below.
Well-Engineered Filtering Banks for Low Temperatures and High Signal Integrity
QFilter-II features two low-pass filtering banks in series: a low-frequency (65 kHz) filter with RC circuits and a high-frequency (RF, 225 MHz) filter with LC circuits. Each bank is crafted with several individually shielded filter stages. Signal lines support 150V voltages (below 4 Kelvin, max. 6mA for RC, 10mA for RF) and provide >10GΩ isolation below 4K to ground and other lines. Individual low-frequency filter lines can be shortened upon request, allowing for higher signal currents e.g. used for current biasing flux-lines.
Scalability for High Channel Demands
For systems requiring more than 24 lines, QFilters can be efficiently stacked (top image) saving space on the mixing chamber plate or connected in series (bottom image) removing the need for jumper cables. This flexibility allows for configurations like dual RC or dual RF filters, catering to diverse setup requirements.
Get the Full QFilter-II Spec Sheet
Key Features
- Effective Electron Temperature Cooling: Reduces electron temperature through filtering to typically 5-15 mK above the mixing chamber.
- Advanced Low-Pass Filtering: Dual filter boards (RC and RF) with 24 channels each for strong noise rejection.
- Effortless Integration: Easily mountable on standard mixing chamber plates of dilution refrigerators with 20 mm x 20 mm pitch.
- Robust and Scalable Design: Sturdy build, suitable for stacking to accommodate higher channel counts.
- Optimal Thermal and Electrical Performance: Thermal anchoring to gold-plated copper brackets and 2GΩ isolation per channel.
- High Magnetic Field Compatibility: Non-magnetic, shielded components including titanium connectors for reliable operation in various environments.
- Connector Compatibility: Equipped with 25-pin microD connectors used in most dilution refrigerators.
- Compact and Space-Efficient: Dimensions of 30 mm x 47 mm x 70 mm for space-sensitive setups.
- Versatile Configuration: Suitable for 48, 96, or more lines, with options for stacking or in-series connections.
Benefits
Rejects Electronic Noise
QFilter including both low frequency and RF filters transmits below 65 kHz and attenuates from 10 MHz to 20 GHz by more than -60dB.
High Magnetic Field Resilience
Designed with non-magnetic, shielded components, QFilter excels in high magnetic fields, offering dependable performance.
Flexible and Scalable Design
Adaptable for filtering 48, 96, or more lines, QFilter’s scalable design meets the demands of growing research projects.
Additional Resources
Scientific Publications
Electron Thermometry
Read More
Scientific Publications
Low-temperature benchmarking of qubit control wires by primary electron thermometry
Read More
Brochures
QFilter-II: Compact Multi-Stage Low-Pass Filter
Read More
Blog
Feedback-Driven Quantum Stabilization: Two-Axis Real-Time Control of Spin Qubits
Read More
Scientific Publications
Electron Thermometry
Read More
Scientific Publications
Low-temperature benchmarking of qubit control wires by primary electron thermometry
Read More
Brochures
QFilter-II: Compact Multi-Stage Low-Pass Filter
Read More
Blog
Feedback-Driven Quantum Stabilization: Two-Axis Real-Time Control of Spin Qubits
Read More
Customers’ Success Using QFilter
Superfluid response of an atomically thin gate-tuned van der Waals superconductor
Apr 2023
Josephson diode effect from Cooper pair momentum in a topological semimetal
Aug 2022
Isospin order in superconducting magic-angle twisted trilayer graphene
Feb 2022
Spin-orbit–driven ferromagnetism at half moiré filling in magic-angle twisted bilayer graphene
Jan 2022
Zero-bias peaks at zero magnetic field in ferromagnetic hybrid nanowires
Sep 2020
Correlated insulating and superconducting states in twisted bilayer graphene below the magic angle
Sep 2019
Superconducting, insulating and anomalous metallic regimes in a gated two-dimensional semiconductor–superconductor array
Aug 2018
Robust anomalous metallic states and vestiges of self-duality in two-dimensional granular In-InOx composites
Mar 2021
Controlled dc Monitoring of a Superconducting Qubit
Feb 2020
Ultra-fast electronic pulse control at cryogenic temperatures
May 2019
Precision measurement of the quantized anomalous Hall resistance at zero magnetic field
Feb 2018
Spin-degeneracy breaking and parity transitions in three-terminal Josephson junctions
Jul 2023
Flip-chip-based fast inductive parity readout of a planar superconducting island
Jul 2023
Demonstration of nonlocal Josephson effect in Andreev molecules
Jun 2023
Sweet-spot operation of a germanium hole spin qubit with highly anisotropic noise sensitivity
May 2023
Why Leading Experts
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Disentangling Losses in Tantalum Superconducting Circuits
“QM’s chip packaging solutions are exquisite pieces of engineering that have enhanced our resonator Q-factors to as much as 200 million. It is clearly a very highly engineered product that I’m sure will be widely adopted in the field.”
Check case study>>
PhD Student, Kevin D CrowleyHouck Lab, Princeton University
iSWAP with multiplexed readout in 10 lines of QUA code
“We were extremely surprised by theflexibilitythat OPX offers and by howmuch easier it makes ourexperiments. Moreover, OPX providesextreme speed-ups. No morefrustration due to long waiting timesfor unwanted results!”
See case study>>
Prof. Tse-Ming ChenNational Cheng Kung University, Taiwan
A partner you can trust
”QM's control electronics provide the best real-time features along with an intuitive and well-documented programming interface. At TII, we successfully controlled a 25-q chip and conducted multiplexed characterization of all qubits using QM’s OPX and Octave. What we appreciate most, however, is the QM’s unwavering support and commitment to helping us achieve our targets, even going so far as to send some of their best scientists when needed.”
Alvaro OrgazLead Quantum Computing Control, TII
Substantially reducing coding complexity and time to results
“OPX has been a powerful enabler in our lab, helping us quickly characterize the performance of our recently discovered qubits.The hardware removes time wasted in uploading and waiting during pulse programming.QUA has substantially reduced the complexity of writing quantum protocols, allowing us to code dynamical decoupling and RB sequences in just a few lines. It remarkably saves our time in optimizing the processes and visualizing the results, allowing us to focus more on understanding the physics of our new qubits.” See case study >>
Prof. Dafei JinAssociate Prof., Dep. of Physics & Astronomy, University of Notre Dame
RT Bayesian estimation for drifts mitigation and improved coherence time
“The OPX’s fast feedback and unique real-time processing capabilities were critical for our experiment.Combining these with the OPX’s intuitive programming and QM’s state-of-the-art cryogenic electronics allowed us to do something that we have dreamt of doing for years.”
See case study >>
Prof. Ferdinand KuemmethProfessor at Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Denmark
Innovative engineering and higher research throughput
“QCage integrates seamlessly into our workflow of preparing and loading QPUs and supports higher throughput in our lab. Our research directly benefits from QCage's innovative design and engineering.”
Prof. Javad ShabaniNew York University
Q-factors as high as 200 million
“QM's chip packaging solutions are exquisite pieces of engineering that have enhanced our resonator Q-factors to as much as 200 million. It is clearly a very highly engineered product that I am sure will be widely adopted in our field.”
Kevin CrowleyHouck Lab, Princeton University
Saved two years of development
“Developing a functional qubit control electronic system absorbs a PhD-student full time at least for two years. QM’S Quantum Orchestration Platform allowed us set up experiments for full qubit characterization in 2-3 days with an undergraduate summer school student.”
Prof. Gerhard KirchmairUniversity of Innsbruck
The QOP dramatically expedites research
“We are very pleased with the Quantum Orchestration Platform (QOP) control solution. It’s remarkably easy to use, reliable, and flexible, supporting our advanced quantum research needs. The QOP dramatically expedites our research. The Quantum Machines customer success team has been instrumental in addressing all our needs to help us to maximize the full potential of the solution. We already use two systems and strongly recommend it.”
See case study>>
Prof. Eli Levenson-FalkUniversity of Southern California
Revolutionizing spin qubit control, all in one box
“The quantum orchestration platform (QOP) platform completely changed the way we control semiconductor quantum dot spin qubits. Key qubit control schemes we previously developed individually using time-consuming hardware description languages are now easily implemented in one box.”
See case study>>
Prof. Dohum KimSeoul National University
Simplified lab workflow and faster runtimes
“Replacing three devices with one synchronized, orchestrated machine tremendously simplified lab workflow. Now our pulse sequences run in a fraction of the time of any other device combo. Plus, we can “talk” to the FPGA in human-speak, to run real-time calculations that were too complicated before! Along with the yoga-level.”
Prof. Amit FinklerWeizmann Institute of Science
This system will revolutionize our space
“The first time I was introduced to Quantum Machines, It surprised me how people were getting so excited about it. Only later did I realize, it was like explaining the value of a Laser before it existed, and all you knew are light bulbs. Today I truly believe that these systems will revolutionize our space.”
Prof. Barak DayanWeizmann Institute of Science
Why Leading Experts
Worldwide Choose
Quantum Machines
Disentangling Losses in Tantalum Superconducting Circuits
“QM’s chip packaging solutions are exquisite pieces of engineering that have enhanced our resonator Q-factors to as much as 200 million. It is clearly a very highly engineered product that I’m sure will be widely adopted in the field.”
Check case study>>
PhD Student, Kevin D CrowleyHouck Lab, Princeton University
iSWAP with multiplexed readout in 10 lines of QUA code
“We were extremely surprised by theflexibilitythat OPX offers and by howmuch easier it makes ourexperiments. Moreover, OPX providesextreme speed-ups. No morefrustration due to long waiting timesfor unwanted results!”
See case study>>
Prof. Tse-Ming ChenNational Cheng Kung University, Taiwan
A partner you can trust
”QM's control electronics provide the best real-time features along with an intuitive and well-documented programming interface. At TII, we successfully controlled a 25-q chip and conducted multiplexed characterization of all qubits using QM’s OPX and Octave. What we appreciate most, however, is the QM’s unwavering support and commitment to helping us achieve our targets, even going so far as to send some of their best scientists when needed.”
Alvaro OrgazLead Quantum Computing Control, TII
Substantially reducing coding complexity and time to results
“OPX has been a powerful enabler in our lab, helping us quickly characterize the performance of our recently discovered qubits.The hardware removes time wasted in uploading and waiting during pulse programming.QUA has substantially reduced the complexity of writing quantum protocols, allowing us to code dynamical decoupling and RB sequences in just a few lines. It remarkably saves our time in optimizing the processes and visualizing the results, allowing us to focus more on understanding the physics of our new qubits.” See case study >>
Prof. Dafei JinAssociate Prof., Dep. of Physics & Astronomy, University of Notre Dame
RT Bayesian estimation for drifts mitigation and improved coherence time
“The OPX’s fast feedback and unique real-time processing capabilities were critical for our experiment.Combining these with the OPX’s intuitive programming and QM’s state-of-the-art cryogenic electronics allowed us to do something that we have dreamt of doing for years.”
See case study >>
Prof. Ferdinand KuemmethProfessor at Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Denmark
Innovative engineering and higher research throughput
“QCage integrates seamlessly into our workflow of preparing and loading QPUs and supports higher throughput in our lab. Our research directly benefits from QCage's innovative design and engineering.”
Prof. Javad ShabaniNew York University
Q-factors as high as 200 million
“QM's chip packaging solutions are exquisite pieces of engineering that have enhanced our resonator Q-factors to as much as 200 million. It is clearly a very highly engineered product that I am sure will be widely adopted in our field.”
Kevin CrowleyHouck Lab, Princeton University
Saved two years of development
“Developing a functional qubit control electronic system absorbs a PhD-student full time at least for two years. QM’S Quantum Orchestration Platform allowed us set up experiments for full qubit characterization in 2-3 days with an undergraduate summer school student.”
Prof. Gerhard KirchmairUniversity of Innsbruck
The QOP dramatically expedites research
“We are very pleased with the Quantum Orchestration Platform (QOP) control solution. It’s remarkably easy to use, reliable, and flexible, supporting our advanced quantum research needs. The QOP dramatically expedites our research. The Quantum Machines customer success team has been instrumental in addressing all our needs to help us to maximize the full potential of the solution. We already use two systems and strongly recommend it.”
See case study>>
Prof. Eli Levenson-FalkUniversity of Southern California
Revolutionizing spin qubit control, all in one box
“The quantum orchestration platform (QOP) platform completely changed the way we control semiconductor quantum dot spin qubits. Key qubit control schemes we previously developed individually using time-consuming hardware description languages are now easily implemented in one box.”
See case study>>
Prof. Dohum KimSeoul National University
Simplified lab workflow and faster runtimes
“Replacing three devices with one synchronized, orchestrated machine tremendously simplified lab workflow. Now our pulse sequences run in a fraction of the time of any other device combo. Plus, we can “talk” to the FPGA in human-speak, to run real-time calculations that were too complicated before! Along with the yoga-level.”
Prof. Amit FinklerWeizmann Institute of Science
This system will revolutionize our space
“The first time I was introduced to Quantum Machines, It surprised me how people were getting so excited about it. Only later did I realize, it was like explaining the value of a Laser before it existed, and all you knew are light bulbs. Today I truly believe that these systems will revolutionize our space.”
Prof. Barak DayanWeizmann Institute of Science
Disentangling Losses in Tantalum Superconducting Circuits
iSWAP with multiplexed readout in 10 lines of QUA code
A partner you can trust
Substantially reducing coding complexity and time to results
RT Bayesian estimation for drifts mitigation and improved coherence time
Innovative engineering and higher research throughput
Q-factors as high as 200 million
Saved two years of development
The QOP dramatically expedites research
Revolutionizing spin qubit control, all in one box
Simplified lab workflow and faster runtimes
This system will revolutionize our space
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